javascript add/subtect for form buttons

Hello all i am looking for some code that will allow me to add or subtract 1 from a value of 0.

Hopefully that makes since. Heres the setup...

I have 2 buttons.... ones a "+" and the others a "-". When the user hits the "+" then it adds one to the name of the item in a hidden textbox like so:

Tomatos 1

If i hit the "-" button it would look like this:

Tomatos 0

And of course i would need to check everytime if the number goes into a negitive and spit out a warning.

I havent been able to find sample code for this nor do know what to even look for.

Any help would be great!

David

 

Ok i found this code:

onclick="document.frmSignIn.textfield222.value+='1'"

Code (markup):

And as u know it adds a "1" to the textbox. however everytime i hit it it still adds a "1"... 11111 etc...

How can i take the default textbox value and add to it like:
Textbox = 0

User clicks the button twice:
Textbox = 2

instead of:
Textbox = 11

Thanks,
David

 

Try this. Haven't checked.

function getValue(){
    txt = document.forms[0].fieldname.value;
    arTxt = txt.split(' ');
    val = arTxt[arTxt.length - 1];
    delete(arTxt[arTxt.length - 1]);
    return [arTxt.join(' '), val]
}

Code (markup):

Using the above code you can separate the name and value. Try it and let me know whether it works or not.

Using this method you can manage any number of fields, provided the number is the last part of the string and is separated with a space.

 

Aragorn:
Thanks for the reply. I have desided to just add a textbox for the number. So can you convert your code you posted to just use a textbox now instread of the item name and value?

Thanks!
David